Technical Field
The present application relates to the technical field of semiconductors, and in particular, to a method for manufacturing a semiconductor structure.
Related Art
Amorphous carbon has typical properties. For example, amorphous carbon has a high etching selectivity and ultraviolet absorption of a low reflectivity with respect to oxides of silicon, nitrides of silicon, and polysilicon. Therefore, amorphous carbon is widely applied to the semiconductor manufacturing process of an advance technology node. For example, the amorphous carbon may be a mask for etching a contact hole, and a mask for an etching process of gate patterning, or may be a sacrificial layer for self-aligned double patterning (SADP).
However, the inventor of this application finds that in existing applications, formed amorphous carbon has a non-uniform thickness. As a result, a pattern that is etched using the amorphous carbon as a mask cannot satisfy the requirements. For example, a position of the contact hole deviates from an expected position, and a shape of the contact hole cannot satisfy the requirements.
Therefore, it is desirable to provide a technical solution to enable improved thickness uniformity of amorphous carbon.